Q1. What are the contributions in this paper?
To diphenylglycoluril ( 2 ), four aliphatic chains were attached, each with a vanillyl alcohol group at the end this paper.
A cage compound derived from cyclotriveratrylene and diphenylglycoluril sub-units
02 Sep 2010-Recueil des Travaux Chimiques des Pays-Bas (Elsevier Science bv)-Vol. 108, Iss: 6, pp 215-218
TL;DR: To diphenylglycoluril (2), four aliphatic chains were attached, each with a vanillyl alcohol group at the end as discussed by the authors, and three of them cyclized to form a cyclotriveratrylene unit.
Abstract: To diphenylglycoluril (2), four aliphatic chains were attached, each with a vanillyl alcohol group at the end. In an acid-catalyzed reaction, three of the vanillyl alcohol groups cyclize to form a cyclotriveratrylene unit. The resulting compound (3) has a well-defined cavity and a free, func- tionalized arm. Cyclization of four vanillyl alcohol groups (5) does not occur, probably for steric reasons.
Summary (1 min read)
Introduction
- Organic molecules containing an intramolecular cavity, as well as a nearby catalytic centre, are currently receiving a great deal of attention as synthetic equivalents of enzymes (so called synzymes)1.
- In a later stage, these groups can be converted into catalytic functions (Fig. 2,A ).
- The presence of these isomers can be seen in the l3C N M R spectrum which shows more than one signal for each carbon atom of 3.
- The authors found that the ratio 3/4 depends on the reaction conditions used.
- CPK models suggest that a "sofa" form of the cyclotetraveratrylene sub-unit in 5 is not possible for steric reasons.
General
- Unless otherwise indicated, commercial materials were used as received.
- Diethyl ether, toluene and hexane were distilled from sodium ketyl, while CHC13 was distilled from CaCl2.
- FAB mass spectra were recorded on a VG ZAB 2F spectrometer (matrix: 3-nitrobenzyl alcohol).
- Ele mental analyses were carried out by the Elemental Analytical Section of the Institute for Applied Chemistry TNO, Zeist, The Netherlands.
4-(6-B rom ohexyloxy)-3-m ethoxybenzaldehyde (1)
- The crude product was crystallized from ether.
- During this addition, the temperature rose to approximately 30°C.
- The resulting mixture was stirred for 1 h, brought to pH 6 with concentrated hydrochloric acid and evaporated under reduced pressure.
- The residue was first purified by gel-permeation chromatography (Sephadex LH-20, eluent CHC13).
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References
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TL;DR: A l'aide de la spectrometrie RMN, on etudie le dedoublement optique du bromochlorofluoromethane qui est inclus dans une cavite de compose chiral le cryptophane C.
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